Note: If a chart update is first published as an LNM and then later as an NM, the chart correction is listed just once and referenced to the earlier LNM publication. A similar relationship exists between CNMs and NMs.

NOAA's Chart Update Service

From this site, you can access the same chart updates that NOAA uses to update their Print-on-Demand paper charts, Raster Navigational Charts (NOAA RNC®), and Electronic Navigational Charts (NOAA ENC®). This site also provides advance notification of chart updates affecting hazards to navigation and other information considered essential for safe navigation, including:

Channel conditions,

Bridge and cable clearances, and

Regulatory changes that NOAA has identified and forwarded for publication in both the LNM and the NM.

Temporary changes to aids to navigation, special published announcements, and other important information affecting navigational safety are not available on this site.

NOAA Chart Update Disclaimer - Please read carefully

While information provided by this website is intended to assist in the updating of nautical charts, it must not be used as a substitute for the United States Coast Guard, National Geospatial-Intelligence Agency, or Canadian Coast Guard Notice to Mariner publications.

The information available on this site is derived from the National Ocean Service’s Critical Chart Corrections database (CRIT). CRIT is an in-house chart production tool, and may contain some naming conventions, textual abbreviations, or acronyms that are unfamiliar to the general public. Channel tabulations, depth legends, depth notes, and chartlets may not be included in chart update listings prior to January 2000, due to ongoing development of CRIT throughout the 1990s.